Adoption of Passive House in British Columbia

by nithya_caleb | September 22, 2018 12:00 am

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By Andrew Larigakis, RIBA, AIBC, MRAIC, LEED AP

Government institutions are recognizing the role the Passive House standard can play in effectively reducing greenhouse gas (GHG) emissions, and are beginning to introduce it into their requirements and codes for all types of new buildings (According to a statement[2] released by the Passive House Institute (PHI) during the 2017 Climate Change Conference COP23 in Bonn, Germany, the United Nations (UN) explicitly mentions Passive House as a possibility to increase the energy efficiency of buildings and thus reduce global warming. ). While different levels of government in various jurisdictions are introducing regulations influenced by Passive House, British Columbia, and the City of Vancouver in particular, is currently at the forefront.

Though the Passive House standard has existed since the mid-1990s and tens of thousands of Passive House-compliant buildings have been constructed worldwide, one can only now see the standard and its approach to green building being embedded into government requirements and building codes outside Northern Europe.

Though not rocket science, meeting the Passive House standard is not easy, and requires changes to the way one thinks about constructing buildings in North America. Instead of focusing on mechanical solutions—which have so far not delivered the promised levels of emissions reduction—the Passive House approach is more oriented to the building envelope. The method requires generous insulation, a high level of airtightness, thermal bridge-free construction, and high-performance windows with mechanical ventilation and high heat recovery efficiency.

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Imposing regulations and providing incentives to apply the standard across the board has the potential for a notable impact on carbon dioxide (CO₂) emissions when compared to the current smattering of “green” projects that do not focus on energy efficiency.

At the federal level, Canada’s commitment under the Paris Agreement is to reduce the nation’s GHG emissions by 30 per cent from 2005 levels by 2030 and 80 per cent by 2050. At the forefront of the federal government’s policy is the “Greening Government Strategy[4],” targeting emissions from government operations. For new government buildings, the goal is to be net zero carbon-ready starting, at the latest, in 2022, and for all major building retrofits, the goal is to be low carbon. The government intends to introduce a “first tier” of stringent model codes for buildings in 2020 (Click here[5] for Canada’s buildings strategy. ). The influence of building envelope-focused Passive House principles on these forthcoming codes remains to be seen.

British Columbia, though, recently introduced the Energy Step Code, a part of the B.C. Building Code (BCBC), providing effective Passive House-related standards for GHG reductions. The City of Vancouver has also set itself aggressive green building goals, supported by regulations and policies—including Passive House—as a path to compliance. Additionally, the City of North Vancouver is moving forward with its own requirements. This city’s most ambitious regulatory regime applies to the new Moodyville neighbourhood where Passive House forms a route for gaining approvals.

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BC Energy Step Code

In April 2017, the B.C. government introduced the multitiered BC Energy Step Code[7] to bring a consistent set of standards for energy efficiency to the many jurisdictions in the province. With the introduction of the new regulation, the province is stripping individual jurisdictions—with the exception of Vancouver—of the power to set their own energy efficiency standards. In place of this power, municipalities may choose from several levels of energy performance from within the BC Energy Step Code.

At its highest levels, or “steps,” the new code requirements approach Passive House standards. For instance, the BC Energy Step Code effectively prioritizes building envelope performance because, under the new regulation, buildings must be tested for airtightness. More insulation and better windows than the typical are needed to meet all but the standard’s lowest level. Also, energy modelling is now required for all projects as the BC Energy Step Code is performance-based rather than prescriptive.

The BC Energy Step Code has two sections:

• one for Part 9 residential buildings, which applies province-wide; and
• a second for multiunit residential and commercial that applies only to Climate Zone 4 (the Lower Mainland, southern Vancouver Island, and southern Okanagan).

In contrast, Passive House requirements are the same across all building types and all climate zones.

For Part 9 residential buildings, the new standard has five steps. It also has four levels for multi-unit residential and three for commercial. To meet Step 5—the highest level for Part 9 buildings—Passive House certification provides a clear route to compliance. Section 9.36.6.3 of the new regulation[8], “Compliance Requirements” states, “Buildings designed and constructed…. to the Passive House Planning Package, version 9 or newer, are deemed to comply.” In the province’s guide to the new standard, Step 5 is described as “equivalent” to Passive House.

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Though the requirements for Step 5 are similar to Passive House, they are not identical. Thermal energy demand is the same for both at < 15 kWh/m²year or peak thermal load < 10 W/m². Air changes per hour (ach) in the code are 1.0 whereas Passive House is slightly more stringent at 0.6. While the BC Energy Step Code has a requirement only covering mechanical energy use intensity (MEUI) with a maximum 25 kWh/m²year, this does not account for auxiliary electricity and domestic hot water. Passive House, in comparison, measures overall primary energy renewable (PER)—the total energy use intensity (EUI) multiplied by a PER factor (i.e. the energy supplied from renewable sources divided by the final energy demand of the building). Passive House sets the PER limit at 60 kWh/m²year (Figure 1).

With multi-unit residential, the steps in the new energy code only go up to four. In this instance, thermal energy demand is again set at < 15 kWh/m²year—the same as Passive House. While the BC Energy Step Code sets a maximum total energy use intensity at 100 kWh/m²year, Passive House has a requirement for PER with, as previously noted, a limit of 60 kWh/m²year.

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Lastly, for commercial buildings, the BC Energy Step Code only goes up to Step 3. Here the thermal energy maximum is increased to 20 kWh/m²year and the MEUI goes up to 120 kWh/m²year, which matches earlier versions of the Passive House standard (Figure 2).

The BC Energy Step Code, though different from Passive House, has made a significant move to the methodology and criteria of the Passive House standard. By explicitly accepting Passive House as an “equivalent” to the highest levels of the regulation for each of the three building types referenced, it has provided building professionals the option of using one universal standard for energy compliance[11].

It remains to be seen how effective the BC Energy Step Code will be in reducing GHGs from buildings. For now, the regulation only applies to Part 9 buildings for the vast majority of the province not in Climate Zone 4. Also, with the stated target of being net zero-ready by 2032 and no interim targets, the BC Energy Step Code in its current form allows municipalities to stay more or less where they are for another decade or so. Indeed, the standard’s guide recommends “at least until 2020, local governments that are considering the application of the BC Energy Step Code on a community-wide scale should only require the lower steps.”

Given the normally slow adoption of change within the building and development industry, the timelines of the mostly voluntary BC Energy Step Code may appear reasonable. However, when one considers the BioScience article, “World Scientists’ Warning to Humanity: A Second Notice[12],” where 15,000 scientists issued a warning of catastrophic environmental collapse, saying “soon it will be too late to shift course away from our failing trajectory, and time is running out,” one knows mankind is up against the clock and losing on climate change. One can only hope individual jurisdictions will show moral leadership and ambition, and move to the highest levels of the BC Energy Step Code as quickly as possible.

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Vancouver embraces Passive House

The City of Vancouver has set a goal of achieving zero emissions in all new buildings by 2030. Interim targets[14] include a 70 per cent reduction in emissions from 2007 levels for new buildings by 2020 and
90 per cent by 2025. The city’s lofty ambition[15] is to “lead the world in green building design and construction.” The Passive House standard is acknowledged and supported by Vancouver as an effective vehicle to achieve this goal.

The embracing of the standard is most apparent in Vancouver’s requirements[16] for rezoning applications. Projects for rezoning are required to meet green building requirements to be “near-zero” or “low-emissions” buildings. The city specifically references the Passive House standard as an accepted route to meet these requirements. Additionally, it accepts the use of Passive House Planning Package (PHPP) modelling for energy code compliance for large non-rezoning buildings.

Meeting the ambitious near-zero or low-emissions requirements of the City of Vancouver’s rezoning program requires adoption of the Passive House methodology whether or not one chooses the Passive House certification route to compliance.

In recent years, the city has made significant efforts to remove regulatory barriers impeding Passive House projects. Vancouver now has several staff members, including two building inspectors, who are trained and certified in Passive House design. For multifamily or duplex projects, zoning regulations[17] have exclusions in area calculations for the additional thickness of insulation typically needed in these types of buildings.

For single-family residences, the city has issued separate guidelines[18]—including numerous zoning relaxations—for Passive House projects. Recognizing high-energy efficiency typically requires thicker insulation, the additional thickness of wall is excluded from floor area calculations. Similarly, there are relaxations of height requirements, rear yard setbacks, and overall building depth for Passive House projects. There are also exclusions for external shading, “roof-mounted energy technologies,” and venting skylights.

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“We are seeing increasing interest in the Passive House standard. Projects are coming forward using Passive House as a tool to meet municipal permitting requirements and drive down GHG emissions,” says Jason Packer, director of green building services at Recollective, a green building consulting firm.

Recently cited data from the City of Vancouver finds there are 34 projects representing 1010 dwelling units approved or being approved with a further 26 projects (630 units) in the works that may or may not proceed to the permits stage. Amongst these Passive House projects[20] are several multi- and single-family residential buildings as well as a fire hall. The Heights[21] by Cornerstone Architecture is a six-storey wood-framed building in the City of Vancouver with 85 rental units and commercial space on the ground floor. It is currently considered the largest Passive House project in Canada. Under construction by the same firm is Spire Landing, also in Vancouver, with four storeys and 95 units. The architects have been able to take advantage of the floor area exemptions in Vancouver’s bylaws for thicker, more heavily insulated walls on these projects. They also feel the city’s enthusiasm for energy-efficient and Passive House buildings has been helpful through the approval process.

Though the use of wood is not a requirement of the standard, virtually all Passive House buildings in British Columbia have been of wood construction because of its low level of thermal conductivity compared to other construction materials. Both the City of Vancouver and the Pan-Canadian Framework on Clean Growth and Climate Change call for a wood-first approach.

The 1400 Alberni Street project by Robert A.M. Stern Architects in association with Vancouver-based MCM Partnership takes Passive House to a new scale. The two buildings—one 43 storeys and the other 48—would, for the moment, be the world’s tallest Passive House towers. The design is an emphatic move away from Vancouver’s standard glass towers with massive thermal bridging through concrete slab extensions to the exterior. As an ambitious Passive House project, the buildings with an overall area of 60,380 m² (650,000 sf) have received considerable enthusiasm and support from the city in its early stages of rezoning.

Rezoning and development permit applications to the city for Passive House projects are growing exponentially. Chris Higgins, a green building planner with the city, says it is “likely Passive House will be used more broadly as a building code compliance and rezoning policy option” in the coming years.

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Passive House in the City of North Vancouver

Playing catch up with Vancouver in reducing GHGs from buildings is the City of North Vancouver. While municipal requirements are rapidly evolving, the city’s overall goals for energy savings are still relatively modest. However, change is on its way. The 2014 official community plan[23] calls for a 15 per cent reduction in GHG emissions over 2007 levels by 2020, and a 50 per cent reduction by 2050. North Vancouver recently adopted the new BC Energy Step Code with a phased implementation. As of July 1, Part 9 residential buildings up to 111 m² (1200 sf) will be required to meet Step 1, while taller structures need to meet Step 3. The code standard for Part 3 residential buildings will be Step 2, while Step 1 is for commercial buildings.

Of particular note in North Vancouver is the Moodyville area[24], a primarily single-family residential area recently rezoned for higher-density housing projects. Seeing an opportunity for advancing its sustainability ambitions in the redevelopment of this area, the City of North Vancouver is offering a density bonus to projects achieving Passive House certification—one of three conforming routes to high-energy efficiency and resultant increased density approval. North Vancouver is also actively promoting Passive House projects with a staff recommendation of prioritized treatment in the processing of permits (This is based on a 2016 Staff Report regarding Moodyville rezoning and development controls.). However, attempts to meet the Passive House standard are being made difficult by North Vancouver’s requirement for new projects to hook up to its hot water district energy system. While the system has its efficiencies, meeting the Passive House standard for primary energy is not easy. It remains to be seen how many larger projects will ultimately go for or gain Passive House certification.

Passive House elsewhere

The influence of the Passive House approach to energy-efficient buildings is not confined to British Columbia. Toronto’s Zero Emissions Buildings Framework[25] introduces an approach to reducing GHG emissions using metrics and strategies familiar to Passive House practitioners. The framework calls for performance-related standards measuring total EUI and thermal demand intensity. New buildings will have mandatory airtightness testing. Additionally, Toronto proposes to measure GHG intensity.

Conclusion

One can see the adoption of the Passive House standard is increasingly being recognized by jurisdictions in British Columbia and elsewhere as an effective way to reduce GHG emissions associated with buildings. While requirements vary between jurisdictions and building types, the standard is explicitly mentioned in new regulations in the province, as well as by the cities of Vancouver and North Vancouver, for meeting the most stringent requirements for energy use. Within the often confusing patchwork of regulations, Passive House provides a single standard and methodology for meeting energy requirements in zoning and codes throughout the province. The standard comes with straightforward energy modelling tools, a consistent methodology, best construction practices, and thousands of precedent projects to assist designers and builders. As municipalities and the province increasingly strive to meet zero or near-zero emissions targets for buildings, one can expect to see increasing reference in regulations and codes to Passive House. With this knowledge, architects, designers, developers, regulators, and contractors have a roadmap for the evolution of the building industry in British Columbia in the era of climate change.

[26]Andrew Larigakis, RIBA, AIBC, MRAIC, LEED AP, is a Vancouver-based architect, certified Passive House designer, and principal of his eponymous studio, Larigakis Architecture, which he founded in 2012. During his 30-year practice, Larigakis has been involved in many award-winning local and international projects. He works primarily on institutional, community, and residential projects, with a particular focus on green design. Larigakis can be reached via e-mail at andrew@larigakis.ca[27].

Source URL: https://www.constructioncanada.net/adoption-of-passive-house-in-british-columbia/

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